DIFFERENTIAL EXPRESSION OF TRANSFORMING GROWTH-FACTOR-ALPHA AND INSULIN-LIKE GROWTH-FACTOR-II IN CHRONIC ACTIVE HEPATITIS-B, CIRRHOSIS AND HEPATOCELLULAR-CARCINOMA

In the present study we investigated the expression of transforming growth factor alpha and insulin-like growth factor II to explain the role of these growth factors in the development of hepatocellular carcinoma from chronic active hepatitis B and cirrhosis, The expression of transforming growth factor alpha and insulin-like growth factor II was tested in 38 tissue samples from patients with chronic active hepatitis B, 32 cirrhosis and 31 hepatocellular carcinoma, by immunohistochemical staining using monoclonal anti-transforming growth factor alpha and anti-insulin-like growth factor II, All patients were seropositive for HBsAg. Transforming growth factor alpha was expressed in 26 (68.4%) of 38 chronic active hepatitis B, 18 (56.3%) of 32 cirrhosis and 16 (51.6%) of 31 hepatocellular carcinoma tissue samples, Transforming growth factor alpha was found in the periportal hepatocytes of chronic active hepatitis B and in regenerating hepatocytes of cirrhotic nodules, In hepatocellular carcinoma tissues, transforming growth factor alpha-containing tumor cells were evenly distributed within the tumor tissues but focal distribution limited to a part of tumor tissues was also observed, The expression of insulin-like growth factor II was observed in 30 (93.8%) of 32 cirrhosis and all the 31 hepatocellular carcinoma tissue samples tested, but not in chronic active hepatitis B samples, Insulin-like growth factor Il was expressed in most hepatocytes of regenerating nodules and in tumorous as well as non-tumorous hepatocytes of hepatocellular carcinoma tissues, The current study indicates that, although enhanced expression of transforming growth factor alpha and insulin-like growth factor II in chronic liver diseases may function in concert in multiple steps of hepatocarcinogenesis, insulinlike growth factor II may play a more predominant role than transforming growth factor alpha in hepatocyte proliferation in regenerating nodules and in tumor cell proliferation in hepatocellular carcinoma tissues.